1. Field of the Invention
The present invention relates to a film forming method by sputtering and a sputtering apparatus thereof.
2. Related Background Art
In these years, high frequency wave applications of an magnetic element have been enlarged in read/write heads, microinductors and micro transformer and the like, and a magnetic thin film having good high-frequency characteristics in a GHz band is needed. Accordingly, research and development relating to these are actively carried out. In order to use a magnetic thin film in a high-frequency band, it is necessary to increase an electrical resistance of the thin film, thereby reducing an eddy-current loss, and increasing a resonant frequency. Methods for increasing the resonant frequency include increasing the anisotropic magnetic field Hk or saturation magnetization Ms, but increasing Hk and Ms at the same time is generally difficult, and they are in a relation of trade-off. However, in recent years, by allowing sputtered particles to enter obliquely a substrate and to be oriented using a sputtering method or an ion beam method, it becomes possible to increase a uniaxial magnetic anisotropy based on the shape effect of crystals, and to increase Hk, too, while maintaining a high Ms.
The oblique film forming broadens on and on the application range, and, as a production method of performing obliquely oriented deposition by causing sputtered particles to enter a substrate obliquely, there is such a film forming structure of a substrate passing type that a substrate passes through the target foreside performing the sputtering operation (Patent Document 1). There is also a method which rotates and controls a substrate holder alone to grow a film obliquely (Patent Document 2).
[Patent Document 1] U.S. Pat. No. 6,818,961
[Patent Document 2] JP-A No. 6-144990